Add an option to accept only JSON Objects

embulk · Aug 31, 2023 · cad1f19 · cad1f19
1 parent 1872ce6
commit cad1f19
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Showing 9 changed files with 115 additions and 26 deletions.
diff --git a/src/main/java/org/embulk/util/json/CapturingDirectMemberNameList.java b/src/main/java/org/embulk/util/json/CapturingDirectMemberNameList.java
@@ -47,14 +47,9 @@ static CapturingDirectMemberNameList of(final List<String> memberNames) {
     JsonValue[] captureFromParser(
             final JsonParser jacksonParser,
             final InternalJsonValueReader valueReader) throws IOException {
+        final JsonToken firstToken;
         try {
-            final JsonToken firstToken = jacksonParser.nextToken();
-            if (firstToken == null) {
-                return null;
-            }
-            if (firstToken != JsonToken.START_OBJECT) {
-                throw new JsonParseException("Failed to parse JSON: Expected JSON Object, but " + firstToken.toString());
-            }
+            firstToken = jacksonParser.nextToken();
         } catch (final com.fasterxml.jackson.core.JsonParseException ex) {
             throw new JsonParseException("Failed to parse JSON", ex);
         } catch (final IOException ex) {
@@ -65,6 +60,15 @@ JsonValue[] captureFromParser(
             throw new JsonParseException("Failed to parse JSON", ex);
         }
 
+        if (firstToken == null) {
+            return null;
+        }
+        // The value must be always a JSON object regardless of |onlyJsonObjects| when capturing by direct member names.
+        if (firstToken != JsonToken.START_OBJECT) {
+            valueReader.skipJsonValue(jacksonParser, firstToken);
+            throw new InvalidJsonValueException("Expected JSON Object, but " + firstToken.toString());
+        }
+
         final JsonValue[] values = new JsonValue[this.size];
         for (int i = 0; i < values.length; i++) {
             values[i] = null;

diff --git a/src/main/java/org/embulk/util/json/CapturingJsonPointerList.java b/src/main/java/org/embulk/util/json/CapturingJsonPointerList.java
@@ -18,6 +18,7 @@
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonPointer;
+import com.fasterxml.jackson.core.JsonToken;
 import java.io.IOException;
 import java.util.List;
 import org.embulk.spi.json.JsonValue;
@@ -71,6 +72,7 @@ static CapturingJsonPointerList of(final List<JsonPointer> pointers) {
      * @param parser  {@link com.fasterxml.jackson.core.JsonParser} to read from
      * @return an array of captured JSON values
      * @throws IOException  when failing to read
+     * @throws InvalidJsonValueException  if the JSON value is not a JSON object while it is configured to accept only JSON objects
      */
     @Override
     JsonValue[] captureFromParser(final JsonParser parser, final InternalJsonValueReader valueReader) throws IOException {
@@ -89,6 +91,10 @@ JsonValue[] captureFromParser(final JsonParser parser, final InternalJsonValueRe
             ;
         }
 
+        if (valueReader.isOnlyJsonObjects() && capturer.firstToken() != JsonToken.START_OBJECT) {
+            throw new InvalidJsonValueException("Expected JSON Object, but " + capturer.firstToken());
+        }
+
         return capturer.peekValues();
     }
 

diff --git a/src/main/java/org/embulk/util/json/CapturingPointerToRoot.java b/src/main/java/org/embulk/util/json/CapturingPointerToRoot.java
@@ -32,6 +32,9 @@ JsonValue[] captureFromParser(
         if (value == null) {
             return null;
         }
+        if (valueReader.isOnlyJsonObjects() && !value.isJsonObject()) {
+            throw new InvalidJsonValueException("Expected JSON Object, but " + value.getEntityType().toString());
+        }
 
         final JsonValue[] values = new JsonValue[1];
         values[0] = value;

diff --git a/src/main/java/org/embulk/util/json/InternalJsonValueReader.java b/src/main/java/org/embulk/util/json/InternalJsonValueReader.java
@@ -32,16 +32,22 @@
 
 final class InternalJsonValueReader {
     InternalJsonValueReader(
+            final boolean isOnlyJsonObjects,
             final boolean hasLiteralsWithNumbers,
             final boolean hasFallbacksForUnparsableNumbers,
             final double defaultDouble,
             final long defaultLong) {
+        this.isOnlyJsonObjects = isOnlyJsonObjects;
         this.hasLiteralsWithNumbers = hasLiteralsWithNumbers;
         this.hasFallbacksForUnparsableNumbers = hasFallbacksForUnparsableNumbers;
         this.defaultDouble = defaultDouble;
         this.defaultLong = defaultLong;
     }
 
+    boolean isOnlyJsonObjects() {
+        return this.isOnlyJsonObjects;
+    }
+
     boolean hasLiteralsWithNumbers() {
         return this.hasLiteralsWithNumbers;
     }
@@ -203,7 +209,7 @@ private JsonValue readJsonValue(final JsonParser jacksonParser, final JsonToken
         }
     }
 
-    private void skipJsonValue(final JsonParser jacksonParser, final JsonToken token) throws IOException {
+    void skipJsonValue(final JsonParser jacksonParser, final JsonToken token) throws IOException {
         switch (token) {
             case VALUE_NULL:
             case VALUE_TRUE:
@@ -295,6 +301,7 @@ private long getLongValue(final JsonParser jacksonParser) throws IOException {
         }
     }
 
+    private final boolean isOnlyJsonObjects;
     private final boolean hasLiteralsWithNumbers;
     private final boolean hasFallbacksForUnparsableNumbers;
     private final double defaultDouble;

diff --git a/src/main/java/org/embulk/util/json/InvalidJsonValueException.java b/src/main/java/org/embulk/util/json/InvalidJsonValueException.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2023 The Embulk project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.embulk.util.json;
+
+import org.embulk.spi.DataException;
+
+/**
+ * Represents an Exception for a JSON value that is invalid against the requirement.
+ */
+public class InvalidJsonValueException extends DataException {
+    /**
+     * Constructs a new {@link InvalidJsonValueException} with the specified detail message.
+     *
+     * @param message  the detail message
+     */
+    public InvalidJsonValueException(final String message) {
+        super(message);
+    }
+
+    /**
+     * Constructs a new {@link InvalidJsonValueException} with the specified detail message and cause.
+     *
+     * @param message  the detail message
+     * @param cause  the cause
+     */
+    public InvalidJsonValueException(final String message, final Throwable cause) {
+        super(message, cause);
+    }
+}
diff --git a/src/main/java/org/embulk/util/json/JsonValueParser.java b/src/main/java/org/embulk/util/json/JsonValueParser.java
@@ -34,14 +34,16 @@
 public final class JsonValueParser implements Closeable {
     private JsonValueParser(
             final com.fasterxml.jackson.core.JsonParser jacksonParser,
+            final boolean onlyJsonObjects,
             final int depthToFlattenJsonArrays,
             final boolean hasLiteralsWithNumbers,
             final boolean hasFallbacksForUnparsableNumbers,
             final double defaultDouble,
             final long defaultLong) {
         this.jacksonParser = Objects.requireNonNull(jacksonParser);
         this.valueReader = new InternalJsonValueReader(
-                hasLiteralsWithNumbers, hasFallbacksForUnparsableNumbers, defaultDouble, defaultLong);
+                onlyJsonObjects, hasLiteralsWithNumbers, hasFallbacksForUnparsableNumbers, defaultDouble, defaultLong);
+        this.onlyJsonObjects = onlyJsonObjects;
         this.depthToFlattenJsonArrays = depthToFlattenJsonArrays;
         this.hasLiteralsWithNumbers = hasLiteralsWithNumbers;
         this.hasFallbacksForUnparsableNumbers = hasFallbacksForUnparsableNumbers;
@@ -56,6 +58,7 @@ public static final class Builder {
         Builder(final JsonFactory factory) {
             this.factory = Objects.requireNonNull(factory);
             this.root = null;
+            this.onlyJsonObjects = false;
             this.depthToFlattenJsonArrays = 0;
             this.hasLiteralsWithNumbers = false;
             this.hasFallbacksForUnparsableNumbers = false;
@@ -87,6 +90,11 @@ public Builder root(final String root) {
             return this;
         }
 
+        public Builder onlyJsonObjects() {
+            this.onlyJsonObjects = true;
+            return this;
+        }
+
         /**
          * Sets the depth to flatten JSON Arrays to parse.
          *
@@ -140,6 +148,7 @@ public Builder fallbackForUnparsableNumbers(final double defaultDouble, final lo
         public JsonValueParser build(final String json) throws IOException {
             return new JsonValueParser(
                     buildJacksonParser(json),
+                    this.onlyJsonObjects,
                     this.depthToFlattenJsonArrays,
                     this.hasLiteralsWithNumbers,
                     this.hasFallbacksForUnparsableNumbers,
@@ -156,6 +165,7 @@ public JsonValueParser build(final String json) throws IOException {
         public JsonValueParser build(final InputStream jsonStream) throws IOException {
             return new JsonValueParser(
                     buildJacksonParser(jsonStream),
+                    this.onlyJsonObjects,
                     this.depthToFlattenJsonArrays,
                     this.hasLiteralsWithNumbers,
                     this.hasFallbacksForUnparsableNumbers,
@@ -195,6 +205,7 @@ private com.fasterxml.jackson.core.JsonParser extendJacksonParser(final com.fast
         private final JsonFactory factory;
 
         private JsonPointer root;
+        private boolean onlyJsonObjects;
         private int depthToFlattenJsonArrays;
         private boolean hasLiteralsWithNumbers;
         private boolean hasFallbacksForUnparsableNumbers;
@@ -240,9 +251,14 @@ public static Builder builder(final JsonFactory jsonFactory) {
      * @return the JSON value, or {@code null} if the parser reaches at the end of input in the beginning
      * @throws IOException  if failing to read JSON
      * @throws JsonParseException  if failing to parse JSON
+     * @throws InvalidJsonValueException  if the JSON value is not a JSON object while it is configured to accept only JSON objects
      */
     public JsonValue readJsonValue() throws IOException {
-        return this.valueReader.read(this.jacksonParser);
+        final JsonValue value = this.valueReader.read(this.jacksonParser);
+        if (this.onlyJsonObjects && !value.isJsonObject()) {
+            throw new InvalidJsonValueException("Expected JSON Object, but " + value.getEntityType().toString());
+        }
+        return value;
     }
 
     /**
@@ -251,6 +267,7 @@ public JsonValue readJsonValue() throws IOException {
      * @return an array of the captured JSON values, or {@code null} if the parser reaches at the end of input in the beginning
      * @throws IOException  if failing to read JSON
      * @throws JsonParseException  if failing to parse JSON
+     * @throws InvalidJsonValueException  if the JSON value is not a JSON object while it is configured to accept only JSON objects
      */
     public JsonValue[] captureJsonValues(final CapturingPointers capturingPointers) throws IOException {
         return capturingPointers.captureFromParser(this.jacksonParser, this.valueReader);
@@ -269,6 +286,7 @@ public final void close() throws IOException {
     private final com.fasterxml.jackson.core.JsonParser jacksonParser;
     private final InternalJsonValueReader valueReader;
 
+    private final boolean onlyJsonObjects;
     private final int depthToFlattenJsonArrays;
     private final boolean hasLiteralsWithNumbers;
     private final boolean hasFallbacksForUnparsableNumbers;

diff --git a/src/main/java/org/embulk/util/json/TreeBasedCapturer.java b/src/main/java/org/embulk/util/json/TreeBasedCapturer.java
@@ -56,6 +56,7 @@ class TreeBasedCapturer {
         this.builderStack = new ArrayDeque<>();
 
         this.hasFinished = false;
+        this.firstToken = null;
 
         this.values = new JsonValue[size];
         for (int i = 0; i < this.values.length; i++) {
@@ -98,7 +99,9 @@ boolean next() throws IOException {
 
         // Deepen the pointer stack when the token is a scalar value, START_ARRAY, or START_OBJECT.
         if (token.isScalarValue() || token.isStructStart()) {
-            if (!this.parsingStack.isEmpty()) {
+            if (this.parsingStack.isEmpty()) {
+                this.firstToken = token;
+            } else {
                 final ParsingContext context = this.parsingStack.getFirst();
                 if (context.isObject()) {
                     final String propertyName = context.getPropertyName();
@@ -252,6 +255,10 @@ JsonValue[] peekValues() {
         return this.values;
     }
 
+    JsonToken firstToken() {
+        return this.firstToken;
+    }
+
     private double getDoubleValue() throws IOException {
         try {
             return this.parser.getDoubleValue();
@@ -452,4 +459,5 @@ private static Map.Entry<String, JsonValue>[] toArray(final ArrayList<Map.Entry<
     private final JsonValue[] values;
 
     private boolean hasFinished;
+    private JsonToken firstToken;
 }
diff --git a/src/test/java/org/embulk/util/json/TestCapturingDirectMemberNameList.java b/src/test/java/org/embulk/util/json/TestCapturingDirectMemberNameList.java
@@ -33,11 +33,11 @@
 
 public class TestCapturingDirectMemberNameList {
     @Test
-    public void testRead1() throws Exception {
+    public void testOrdinaryRead() throws Exception {
         final JsonFactory factory = new JsonFactory();
         final JsonParser parser = factory.createParser(
                 "{\"foo\":{\"ignored\":[1,2,{},\"skipped\"]},\"bar\":[true,false],\"baz\":null,\"qux\":{\"hoge\":\"fuga\"}}");
-        final InternalJsonValueReader reader = new InternalJsonValueReader(false, false, 0.0, 0L);
+        final InternalJsonValueReader reader = new InternalJsonValueReader(false, false, false, 0.0, 0L);
 
         final CapturingDirectMemberNameList capturingMembers1 = capturingMembers(
                 "bar",